This invention relates generally to fabricating a fiber-reinforced article and particularly to fabricating the article by a vacuum assisted molding process using membrane.
Composite articles made from a fiber-reinforced resin matrix that are to be used at relatively elevated temperatures are known. By way of example, such composite articles can include jet engine blades, jet engine nacelles, boat hulls, car bodies and components, wind turbine blades, aircraft structures such as wings, wing parts, radar domes, fuselage components, nose cones, flap tracks, landing gear and rear bulkhead. The reinforcing fibers used in the composite article may be any suitable technical fiber such as fiberglass, carbon, aramid, ceramic, hybrid and the like. Depending on the service that the composite article is going to be put into, the article may be manufactured with a resin applied at an elevated temperature so the surface tension of the resin is relatively low.
The known composite articles may be fabricated by infusing resin into a fiber-reinforced layer with vacuum. Laminated sheet material is placed adjacent the fiber-reinforced layer. The laminated sheet material includes a membrane. It is known that the resin is introduced to the fiber-reinforced layer at relatively high temperatures so that the resin has a relatively low surface tension. The resin can, at times, wet or leak through the membrane. When wetting or leaking occurs the molding process is rendered less effective.
Therefore, a need exists for an improved membrane structure that can better resist wetting or leaking through the membrane for use in vacuum assisted molding operations with resins at a relatively high temperature and/or that have relatively low surface tensions.